Plurality of structurally identical spectrometers and a calibration method therefor

In accordance with a method for calibrating structurally identical spectrometers for constituent analysis, a multiplicity of samples are provided and concentrations of one constituent in the individual samples are measured using a reference measuring method. Spectra of the individual samples are measured using one spectrometer selected from the structurally identical spectrometers to determine a preliminary regression model. At least one spectrum is selected from the measured spectra and/or a mean value spectrum formed from the measured spectra. A multiplicity of error spectra are generated using a mathematical model of the structurally identical spectrometers. The individual error spectra are added in each case to the individual selected spectra to obtain simulated spectra. As a result, a resultant regression model is determined in which amplitude values of the measured spectra and selected simulated spectra form the independent variables and in which the reference measurement values form the dependent variable.